Clamp



March 3, 1931. 5, MUELLER 1,794,976

CLAMP Filed Sept. 30. 1929 In Ill 72 Patented Mar. 3, 1931 A UNITEDSTATES PATENT OFFICE s RALPH S. MUELLER, OF CLEVELAND HEIGHTS, OHIO,ASSIGNOR To MUELLER ELECTRIC COMPANY, A PARTNERSHIP COMPOSER) OF RALPHB. MUELLER AND MAUDE K.

MUELLER CLAMP Application filed September 30, 1929. Serial No. 398,331.

larly clamps for use in connection with certain electrical apparatus.'More particularly, the invention relates to a ground clamp for use inconnection with radio apparatus.

The principal object of the invention is to provide a clamp which can beproduced inexpensively, and which has the requisite strength andrigidity to permit a severe clamping pressure to be exerted between therelatively movable elements of the clamp,

- though what may be termedv inexpensive metal is employed inconstructing the clamp body.

The invention may be herein briefly summarized as consisting in a clampwith parts arranged and constructed as described herein and set forth inthe appended claims. 11;

In the accompanying sheet of drawings, wherein I have shown thepreferred embodiment and certain slight modifications of the invention,Fig. l is aside view of the ground clamp with a portion broken away, thesame being cqnstructedin accordance with the inventionIf-Fig. 2 isatransverse sectional view of the saine, substantially along the line 22of Fig. 1; Fig. 3 is a top plan view of the same; Fig. 1 is a plan viewof a stamping from which the clamp body is formed; Fig. 5 is a viewsimilar to Fig. 1 showing a slight modification; Fig. 6 is a similarview showing a still further modification; Fig 7 is a sectional planview of Fig. 6, the section being taken substantially along line 7--7 ofFig. 6; and F ig'. 8 is. a view similar to Fig. 1 showing the clamp ofthat figure but adapted for a different use than as a ground clamp,

My improved clamp, in all of its forms, 1ncludes a body 10 which issubstantially semicircular in outline, this body being formed of sheetmental and being substantially U- shaped in cross-section, as clearlyindicated in Fig. 2 and some of the other figures. At one end of thebody 10, clamping or holding portions, in this instance the equivalentof jaws 11 are formed in the side walls of the U- shaped section and atthe opposite end of the body 10, a clamping screw 12 is mounted oppositethe jaws and centrally with respect thereto in both directions, as willbe more fully described presently. It is between the clamping screw 12and jaws 11 that the other .part, whatever, it may be, is securelyclamped to form the necessary electrical connection therewith. When theclamp is used as a ground clamp, the electrical connection with theclamp body is made through the medium of a small screw 13 engaging atapped hole at about the middle point of the body, as indicated in Figs.1 and 2 and other figures. When the device is used as a ground clamp, itwill be clamped to a pipe or similar grounding member.

The clamp body 10 is, as above stated, formed of sheet metal and when itis-constructed as shown in Fig. 1, it is formed or shaped from astamping 14, as shown in Fig. 4. It is a feature of the invention inview of the strength attained by the form of the clamp body and byreason of the manner of mounting the clamping screw 12, that inexpensivesheet metal may be employed, as compared with other devices now in usehaving a clamp body so formed that to attain the requlsite strength, themetal must be hardened. In contradistinction to this, I employ a clampbody so formed that no hardening is required, thus making it possible touse cheaper material.

This stamping 14: can in one operation of apress be given thesemi-circular outline or form and U-shaped cross-section indicated nFig. 2, which shows the inwardly extendlng sides or flanges of the bodyspaced a suitable'distance apart and in parallel relation, it beingdesired that the jaws 11, which are provided in the flanges, at one endof the body 10 be a certain distance apart to give stability in theclamping operation.

The manner of mounting the clamping screw forms an important feature ofthe invention for the efliciency of the device depends, not only on theform and strength of the clamping body, but on the mounting of theclamping screw. Preferably, this screw is mounted in and has threadedengagement with two portions of the clamp body, spaced longitudinally ofthe screw. In the preferred embodiment, one end of the blank 14 isprovided with a laterally projecting ear right angles into engagementwith 15 and" at the time that the body is formed from the blank orsubsequent to the forming step, this ear is bent laterally across theinnerside of the clamp body so as to bridge the space between theflanges, as best shown in Fig. 3. Both this ear and the rear wall of thebody'oppositethe ear are provided with aligned openings, both of whicharepreferably threaded to accommodate the screw 12. These screwsupporting walls are in Fig. 1. This feature of the centralized screwand the construction which keeps it centralized with reference to thejaws in both planes or in both dlrections is Important for .the reasonthat it enables a very severe clamping pressure to be exerted on thepipe or element to which the device is clamped without a skewing orlateral displacement of either the jaws with reference to the screw orof the screw with reference to the jaws,

the arrangement being such that the point of the screw and the jaws arepresented squarely to the surface of the part to be engaged by theclamp, enabling a good biting contact to be obtained as is oftendesirable and in fact necessary when a. pipe or other member iscorroded, coated or painted.

,Instead of the ear being formedso as to project laterally from one endof the blank, as shown in Fig. 3, it may be formed at the end of theblank in line with the center thereof, as indicated at 15a, in Fig. 5,the .ear being bent inwardly and then downwardly1t Iat having a slottedhead to accommodate a screw-driver or a head of the wing nut type may beemployed or the head may be of any other suitable shape as will bereadily appreciated.

The invention is not confined in its use to a ground clamp, but may beemployed .for making other electrical connections and, when the clamp isemployed for certain uses, the conductor which is attached to the clampmay be too large to make it convenient or desirable to attach it to theclamp body by meansof the screw 13. For example, the clamp with asuitable conductor attached thereto or two clamps joined. together by aflexible conductor may be employed advantageously with certain batterycharging equipment, one clamp being designed to make electricalconnection with the terminal of the battery and the other with a currentsupplying bus bar. The shape of the body 10 lends itself very readily tosuch additional uses for it is very convement, for example,to extend aconductor, such as indicated at 17, into the U-shaped body at the jawend and to solder or otherwise attach the uninsulated end of theconductor to the base wall of the clamp or to either of the flanges forthat matter as indicated in Fig. 8. Wit this method of attaching theclamp body to the electrical conductor, the connecting screw 13 will bedispensed with. The construction shown in'Fig. 8 is otherwise similar tothat shown in Figs. 1 to 3, and further explanation is deemedunnecessary, this fignotched portions of the side flanges so as tosureserving to indicate that the clamp may be produce an inner screwsupporting wall shown in Fig. 5. With this arrangement of the ear, theclamp body is not so readily formed but this is wholly or partiallycompensated for by the fact that a saving of metal, is "-efiected "inthe production of the blanks, there being less scrap than when the earis arranged as in Fig. 4. Though the two clamps are operated with thesame efiiciency, I refer that shown in Figs. 1 to 3.

11 Figs. 6 and 7, I have indicated another way of mounting the screw. Inthis instance, I suitably mount a nut 16 in the end of the clamp bodyand in the oppositely disosed or parallel side flanges of the clamp ody.The screw has threaded engagement with the nut and sliding or centeringengagement with the wall of the clamp body opposite or in line with, thenut. Here again, the screw is mounted in two members. spaced apartlongitudinally of the screw and used for making other electricalconnections than is required of a ground clamp.

It will thus be seen that I have provided a clamp adapted for differentpurposes or with different electrical apparatus and which can beproduced" in quantities inexpensively but which is nevertheless veryserviceable and so formed that it is only necessary to place the deviceto be clamped between the jaws and the point of the screw and to tightenthe screw which remains centralized irrespective of the pressure whichis applied.

In the appended claims the ends of the clamp body are defined as beinadjacent each other. I mean by this that 1n bending the stampin 14 tosubstantially semi-circular outline t e ends are brought closer togetheror are more closely spaced than in the original straight stamping.

. I do not desire to econfined to the exact details or arrangementsshown, but aim in my claims to cover all modifications which do notinvolve a departure from the spirit and scope of the invention.

Having I claim 1s 1. A clamp of the character described comthusdescribed my invention, what prising a body formed from a stampin bentsubstantially U-shapein outline with 1ts opposite ends adjacent eachother and to su stantially U-sha e in cross-section with inwardlydirected anges and having clamping portions at one end and a clampingscrew at the other end.

2. A clamp for the purpose describedformed from a sheet metal stampingbent into substantially U-shape so that the opposite ends are adjacenteach other and flanged inwardly so as to be channel-shape incross-section, one end of the body having jaws formed in the flanges andthe other end of the bodiyl' carrying a clamping screw centralized witIn testimony whereof, I hereunto afiix my signature.

RALPH S. MUELLER.

